1. Field of the Invention
The invention relates to the method of positionally fixing a tab on a sheet metal lid for attaching to a body of a beverage can.
2. Discussion of Background Information
When the tab is in an attached condition to the sheet metal lid, it is known by the expert as a SOT (Stay on Tab), which is provided for opening an openable area in the surface of a lid (usually designated as “panel”). For this purpose, the tab is taken at a grip end and raised with a vertical tilting motion for breaking open an openable area along a line of weakness (usually called score line) with its opening end.
Particularly when large opening ends (LOEs) are used for the openable area, difficulties are encountered in the related art when fixing the positions of the tab in an attached condition to the sheet metal lid. Suggestions on this topic have already been made, for example in U.S. Pat. No. 5,799,816 (Schubert). In this document, a breaking-through of an attaching portion of the tab is proposed, which attaching portion is usually designated as “rivet island”. The attaching portion is secured to the panel of the sheet metal lid through a shaped rivet and overlaps a round to elongated reformed bead with an opening provided in the attaching portion. The bead may also be formed after attaching the tab, compare column 3, lines 63–67, column 5, lines 37–44, claim 3 of the above-noted document and the associated graphical illustration in FIGS. 2 and 4 thereof.
The invention addresses the technical problem of achieving the same effect, but with an improved manufacture and reliability of the anti-rotation block and with an improved positional alignment of the tab in the attached condition. For this purpose, a method is proposed.